Roll‐to‐roll manufacturing method of aqueous‐processed thick LiNi0.5Mn0.3Co0.2O2 electrodes for lithium‐ion batteries

• Published in: International journal of energy research Vol. 45; no. 15; pp. 21182 - 21194
• Main Authors: Demiryürek, Rıdvan, Gürbüz, Nergiz, Hatipoglu, Gizem, Er, Mesut, Malkoc, Hasan, Guleryuz, Ozkan, Uyar, Gulsen, Uzun, Davut, Ateş, Mehmet Nurullah
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Inc 01.12.2021; Hindawi Limited
• Subjects: aqueous processing; Aqueous solutions; Batteries; Binders; Butadiene; Carboxymethyl cellulose; Carboxymethylcellulose; Cathodes; Cathodic cleaning; Cellulose; Coated electrodes; crack‐free coating; Drying; Electrochemical analysis; Electrochemistry; electrode manufacturing; Electrodes; Ethene; Ethylene; Ethylene oxide; Feasibility studies; Lithium; Lithium-ion batteries; Manufacturing; Mass; Multilayers; Polyethylene oxide; Production methods; Slurries; Stability; Styrene
• ISSN: 0363-907X; 1099-114X
• DOI: 10.1002/er.7171

Summary Aqueous‐based slurry media for cathode electrode production offers a cleaner and safer environment during the electrode manufacturing step compared with the conventional organic solvent‐based method used in the lithium‐ion battery industry. In this work, carboxymethyl cellulose (CMC), styrene‐butadiene rubber (SBR), and poly(ethylene oxide) (PEO) water‐based binders are used to prepare LiNi0.5Mn0.3Co0.2O2 (NMC) cathode electrode. Detail electrochemical analysis reveals that the optimum mass ratio of CMC:SBR mixture is 1:2 when preparing an aqueous slurry for the NMC electrode. To mitigate particle cracking phenomenon during electrode drying step and obtain higher mass loading, a multi‐layer coating technique is implemented. CMC‐PEO binder mixture in aqueous media is also studied as an alternative aqueous processing method for NMC electrodes. The electrodes prepared with CMC‐PEO mixture are demonstrated to be all crack‐free, and electrochemical results indicate that the optimum mass loading of NMC electrode is between 15 and 18 mg cm−2. This method is further tested in pouch cell format using a roll‐to‐roll pilot‐scale production line to show the feasibility for commercial applications. Remarkably, pouch cell results manifest that aqueous‐processed NMC cathode against graphite anode maintains its 89% capacity at 1C even after 1000 cycles. Highlights Water‐based binders of carboxymethyl cellulose‐poly(ethylene oxide) provide excellent cycling stability for LiNi0.5Mn0.3Co0.2O2 electrode. Multilayer coating allows electrodes for higher loadings without any crack formation. The water‐based electrode preparation method is validated by pilot scale roll‐to‐roll electrode production line.